1. Field of the Invention
This invention relates to an omnidirectional motorized wheelchair having front wheels consisting of two independent casters, and rear wheels consisting of two independent motor-operated wheels, and more particularly to an omnidirectional motorized wheelchair, which can be operated by a rider with the rider remaining to face in the forward direction, so as to be moved straight or turned even in a lateral direction, and which can be moved to a desired place easily and reliably with the wheelchair facing in any direction, by using a combination of the mentioned novel wheelchair-operating techniques and conventional wheelchair-advancing, retreating, turning and direction-changing techniques.
2. Description of the Prior Art
A conventional motorized wheelchair generally has front wheels consisting of a pair of casters, and rear wheels consisting of a pair of motor-operated wheels fixed to a wheelchair body and driven independently of each other by reversible, varying-speed DC motors. The direction of rotation and rotational speeds of the right and left motor-operated wheels are varied by reversing the power source connection of the DC motors and regulating input voltages therefor, to thereby vary the direction of movement of the wheelchair. Thus, a conventional motorized wheelchair can be advanced, retreated, turned to right and left, and turned round in a stopped state, very easily. However, this conventional motorized wheelchair having motor-operated wheels fixed to the wheelchair body cannot be moved laterally with a rider remaining to face in the forward direction. A conventional motorized wheelchair, to which front wheel control units for automobiles are applied, does not permit its motor-operated wheels to be directed sideways with respect to a rider, and cannot be moved laterally with the rider remaining to face in the forward direction. Accordingly, the rider on such a motorized wheelchair cannot carry out such kind of work that requires his wheelchair to be moved laterally with his body left directed forward. Namely, the rider on such a wheelchair cannot, for example, write letters on a blackboard smoothly, or apply paint on a wall easily, and feels great inconvenience.